A 78-year-old grandmother has been handed a suspended jail sentence for running over and killing a pregnant mother.

Clare Hansson pleaded guilty to dangerously operating a vehicle causing death after she struck and killed 33-year-old Kerryn Blucher at the Redland Spring Festival at Cleveland, east of Brisbane, in September 2012.

The court heard that Hansson was performing at the festival as a musician, but when she tried to back out of the showground car park she accidentally struck two bollards, panicked and began driving "irrationally".

The victim's husband, Vaughan Blucher, was at the festival when his wife died, and told the court that since then his life has been a state of confusion, despair and sadness.

"In a split second in time, my life and aspirations were shattered," he said.

Ms Blucher was 35 weeks' pregnant when she died, along with her unborn baby girl who would have been named Olivia.